Large-scale analysis of gene expression, protein localization, and gene disruption in Saccharomyces cerevisiae.

We have developed a large-scale screen to identify genes expressed at different times during the life cycle of Saccharomyces cerevisiae and to determine the subcellular locations of many of the encoded gene products. Diploid yeast strains containing random lacZ insertions throughout the genome have been constructed by transformation with a mutagenized genomic library. Twenty-eight hundred transformants containing fusion genes expressed during vegetative growth and 55 transformants containing meiotically induced fusion genes have been identified. Based on the frequency of transformed strains producing β-galactosidase, we estimate that 80-86% of the yeast genome (excluding the rDNA) contains open reading frames expressed in vegetative cells and that there are 23-135 meiotically induced genes